[PATCH] Remove TAB in mk.sys

[Purple Rain]

? sys.mk.diff
Index: sys.mk
===================================================================
RCS file: /cvs/src/share/mk/sys.mk,v
retrieving revision 1.93
diff -u -p -r1.93 sys.mk
--- sys.mk      4 Mar 2023 14:49:37 -0000       1.93
+++ sys.mk      8 Mar 2023 00:20:15 -0000
@@ -44,7 +44,7 @@ COMPILE.cc?=  ${CXX} ${CXXFLAGS} ${CPPFLA
 LINK.cc?=      ${CXX} ${CXXFLAGS} ${CPPFLAGS} ${LDFLAGS}
 
 CPP?=          cpp
-CPPFLAGS?=     
+CPPFLAGS?=
 
 FC?=           f77
 FFLAGS?=       -O2